Texas root rot, caused by the fungus Phymatotrichum omnivorum, which lives in the soil. This vine fungal disease can prevent grape-growing in parts of the south western United States. A circular patch of vines can suddenly die in summer. The disease is avoided by planting disease-free material in non-infested soil. The vigorous rootstock Dog Ridge can be planted where the fungus is suspected.
© Jancis Robinson and Oxford University Press 1994, 1999, 2006, 2015